Generally, a phenomenon that an engine rpm or a turbine rpm increases abruptly due to a delay in an increase of hydraulic pressure, which is caused by a shortage of hydraulic pressure in a hydraulic pressure control line in an automatic transmission of a vehicle, is generally referred to as a blow-up phenomenon. For example, during a power-on 2-3 upshift, if hydraulic pressure for off-going friction element, which is to be released in a target shift ratio, is previously released in a state that hydraulic pressure for on-coming friction element, which is going to be engaged in a target shift ratio, is not sufficiently increased to a level in which the on-coming friction element is able to cover an input torque, a turbine rpm may abruptly increase.
In order to prevent such blow-up phenomenon, a compensation is generally performed with respect to the hydraulic pressure acting on the on-coming friction element.
However, when there is an excessive blow-up, such conventional hydraulic pressure compensation is not sufficient for suppressing the blow-up phenomenon. In addition, if an additional shift control for suppressing the blow-up phenomenon is performed, an overall shift control becomes complex and an unexpected shift shock may occur.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is already known to a person skilled in the art.